An Indian teenager, his family killed in a shipwreck, must navigate a small boat across the Pacific Ocean with no company but a ravenous Bengal tiger. Both creatures endure a rite of passage in Ang Lee’s visually spectacular, emotionally resonant film of the Yann Martel novel. Pi, played by Suraj Sharma as a boy and Irrfan Khan in the framing story, channels millennia of seafaring heroes, from Noah to Ulysses, and centuries of solitary survivors, from Robinson Crusoe to the Tom Hanks character in Cast Away. But the real wonder of Pi is Lee’s poetic use of 3-D — conjuring a looking-glass ocean, schools of flying fish and about a million meerkats — and the motion-capture technology that put an imaginary tiger in a real boat. The line of ascension runs from Avatar to Rise of the Planet of the Apes to this entrancing feat of magical realism.