Antiphospholipid syndrome (APLS) is characterised by venous or arterial thrombosis and/or adverse pregnancy outcome in the presence of persistent laboratory evidence of antiphospholipid antibodies. Catastrophic Antiphospholipid Syndrome (CAPS) is a severe and rare form of antiphospholipid syndrome characterised by multiple site thrombosis involving small, medium and large blood vessels occurring over a short period of time (usually 1 week) causing multiorgan failure. We present an unusual case of left upper limb acute arterial thrombosis with purpura fulminans like skin lesions precipitated by swine flu (H1N1) infection with adult respiratory distress syndrome subsequently developing acute renal failure, retinal infarcts, multiple acute cerebral infarcts, cardiac valvular vegetations and hemolytic anemia with recurrent bleeding episodes. A positive lupus anticoagulant confirmed the diagnosis of CAPS. In spite of early initiation of triple therapy (anticoagulation, high dose steroids, plasmapheresis) our patient did not survive. This rare case of probable CAPS is presented with an aim to study the clinical manifestations, laboratory findings, efficacy of therapy and prognosis in the medical ICU.