Covert police video played in B.C. Supreme Court on Wednesday shows the undercover officer telling Nuttall he will help track down whatever supplies are needed but that Nuttall must be realistic.
"This thing has to be prepared. It has to be researched," says the officer, posing as an Arab businessman and whose identity cannot be revealed.
"I'm here to make what you have in your head become true, what you want in your heart to be reality. That's what I'm here for."
The video, which was shot in early May 2013 as part of a police sting, shows Nuttall and the officer conversing in the front of a pickup truck.
Nuttall is seen with long hair and a scraggly beard, sporting a black leather jacket done up over a tasselled scarf.
Less than a week earlier, the officer drove Nuttall and his wife and co-accused, Amanda Korody, to Whistler to drop off a hard drive containing an outline of Nuttall's planned Via Rail hijacking to one of the officer's associates.
Moments after handing over the outline — most of which Nuttall finalized minutes earlier in a Whistler parking lot — he begins speaking about a revised plan to attack a nuclear submarine stationed off the east coast of Vancouver Island.
"You cannot just talk about this thing (off the) top of your head," the officer tells him in their subsequent meeting.
The officer also says he has convinced his associates to give Nuttall a second chance.
"If you want something to be done, do your research."
Both Nuttall and Korody have pleaded not guilty to four terrorism-related charges after they were arrested for allegedly planting homemade pressure-cooker explosives on the grounds of the B.C. legislature on Canada Day 2013.
In another audio recording played to the court on Wednesday, Nuttall lists the supplies needed to carry out his initial train-hijacking plan.
Included on his supply list are steel-toed boots, "Teflon-coated" bullets, "frag" grenades, cellphones, canteens and suicide vests.
Nuttall also lists AK47 assault rifles, which he says the public will recognize from the movies and immediately associate with Islamic terrorism.
Moments after Nuttall commits to kill all the non-Muslim, male hostages in the train hijacking plot, Korody presses the undercover officer to find someone to look after the couple's cat after they are gone.
"(She's) a beautiful cat, wonderful personality, but obviously under the circumstances we … need to find someone who will care for her," says Korody.
"Preferably a Muslim," adds Nuttall.
The court has previously heard that Nuttall and Korody recently converted to Islam and plotted their attack to avenge what they viewed as the mistreatment of Muslims overseas.
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